Nozzle block



Dec. 28, 19262. V A1,612,436

F. HODGKINSON NOZZLII BLOCK Filed peo* 21, 1923 2 sheets-sheet 1 se 3ef%3.7 '57 (al k 36 (2a EHoa'qk/'nsan INVENTOR ATTORNEY l F. HODGKNSONNOZZLE BLOCK Filed Dec. 21, 1923 2 shets-sheet 2 f.' #odg/rin san VINVENTOR .Q BY

ik ATTORNEY Patented Dec. 28, 192.6.

UNITED STATES PATENT oFFlcE.-

FRANCIS HODGKINSON, F S'WARTHMORE, PENNSYLFANA, ASSIGNOR TO WESTING-HOUSE ELECTRIC 8c MANUFACTURING' CMPAIIY, A CORFORATION OF PENNSYL-VANIA.

NOZZLE BLOCK.

Application filed. DecemberZl, 1923. Serial No. 682,118.

My invention relates to nozzle bloc-ks as employed in fluid pressureturbines and 1t fre has for its object to provide a device of the view,partially in section, illustrating` three blade rows as employed with anozzle block ,rf my improved construction; Fig. 3 is a cross-sectionalview of an assembled nozzle block taken on the plane III-III of Fig. 2;Fig. 4 is an exploded View of my nozzle block, clearly illustrating thecontour and relationship of the respective portions thereof; Fig. 5 is aside view, in elevation, of au assembled nozzle block embodying myinvention; Fig. 6 is a plan View of a modified nozzle block for use withradial flow t-urbines; Fig. 7 is a side view of one-half the nozzleblock shown in Fig. 6; Fig. 8 is a cross-sectional View of the half1member shown in Fig. 7 taken on the plane VIII-- VIII; and Fig. 9 is aplan view of a partition or septum member to be employed in defining thedistinctive nozzle passages in the structure of Fig. 6.

In the construction of nozzle blocks as employed in fluid pressureturbines, it has been usual to employ rather complicated castings,involving considerable labor and expense to finish in proper form.`Furthermore, 'dierent patterns, etc. have been necessary whenconstructing nozzle blocks of dierent capacities, it being well-knownthat turbines having the same frame and spindle are supplied with nozzleblocks hav-- ing differing numbers of nozzle passages and differentareas of nozzle passages in order to provide for different steam pres-00 sures, etc. and for different desired loads.

To maintain the patterns, etc. for supplying nozzle blocks of thesevarious types has been a great expense.

In accordance with the present invention, I mill out complemental spacesin the faces of two forgings, said complemental spaces being adapted,when the members are fitted together, to define a nozzle space. Suitablepartition or septum members are mounted between the two main membersland serve to divide said main nozzle space into a plurality of nozzlepassages. Hence, by the use of differing milling cuts, I may vary thesize of the nozzle passages in thev completed nozzle block and,furthermore, by forming more or less of said passages, I may increase ordecrease the capacity of the block. All of said parts are firmly brazedor welded together after assembly, so as to form a unitary structure ofgreat rigidity, as 1s demanded.

Referring to the drawing for a more detailed understanding of myinvention, I show a turbine casing at 11 in Fig. 1 having a steam chest12 mounted at the end thereof as is the usual practice. Steam issupplied to the turbine through a line 13, suitable branch lines 14H-141leading from the primary, secondary and tertiary control valves at 15and the steam passing to suitable nozzle blocks disposed within themembers 16- 16, all as is well-known to those versed in the art.

Referring to Fig. l2, I show two rows of moving blades yof the impulsetype at 17 cent the first row of moving blades 18 and separated by a rowof fixed blading 19.

A nozzle block 20, constructed in accordance with my invention, isdisposed adjacent the first row of moving blades 18 and is segmental inshape as shown in Fig. 5,

. embracing a greater or less number of blades dependent upon the ratingof the turbine and upon the properties of the steam which it is desiredto employ. The nozzle block 20 embodies a plurality of nozzle passages10-10 formed as hereinafter described tol take steam from the steamchest and suitably expanding the same for impact upon the blades 18.

Referring more particularly to Figs. -l and 5, the nozzle block 20comprises an outer arc-shaped member 21 and an inner arcehaped member 22concentrically disposed with respect thereto, these two members togetherdefining a nozzle space which is divided into individual nozzle passagesby partition members shown more clearly at 23 in Fig. ll. A s furthershown in Fig. 4, the member' 2l is milled at 24 to define a portion otan inlet chamber, a. throat portion 25 and a divergent portion 26.Similarly, the member 2l is milled to partially define an adjacent steampassage by the formation ot a portion ot a steam inlet chamber at 27, athroat portion at 28 and a steam expanding portion 29. Similarly, at 30l show portions ot still another nozzle passage.

ln like manner, the inner arc-shaped member 22 is milled at 31 Atodeiine a steam inlet chamber portion complemental to that shown at 24,together with a throat portion at 32 complemental with that shown Vat25, and with a steam-expanding passage at yconfiplemental with that at2G.

Similarly, thel portion 34 of the member 22 is shaped to complete asteam inlet chamber by coaction with the portion 27 ot the member 2l, athroat portion 35 is complemental with that shown at 28, and asteamexpanding passage, partially deined at 3G, is complemental to thatshown at 29.

`Separating the partially defined steam passages in the member 2l areslots 36-36 and similarly separating the partiallyformed nozzle-passagesin the member 22 are slots 37-37 The partition, or septum, members 23are similar in conliguration, preferably being formed ot pressed steel,and embody relatively wide portion 3S followed by a portion 39 narrowingin width and also tapering in thickness by virtue et being chamte-redaway, as shown at Ll0. Preferably the partition `is chamtered away tosuch `an extent as to terminate in a sharp edge,

short ot the outer plane ot the nozzle block, whereby the steam jetsissuing from the respective jets merge into one stream tor impact uponthe blading. At the head end ot the portion 38 is tor-med a notch 4lvsurrounded by a flange 42 to assist in defining the entrance tothesteam inlet chamber tor the associated Inozzle passage.

In assembling the parts thus shown to build up the structure shown inFig. 5, the member 22 is placed in concentric relation to the member 2lso that complemental por- 'tions ot the milled surfaces thereot= coactto partially detine steam passages. rlhe partition members 23 are thenslipped into the grooves 36-37, one between each pair of adjacent steampassages, so as to completely define these passages.

t will be noted that the steam passages thus defined are substantiallyrectangular in cross section, and as shown in Fig. 2, the members 23H23lie in substantially parallel relationship. The portions 26 and 29 yotthe member 2l and portions 33 and 36 ot the member 22, however, are sorelieved or cut away as to cause a slight increase in the cross sectionet' the nozzle passages toward the discharge end, thus permitting anydesired pressure-velocity conversion in the steam.

After the members 2l, 22 and 223-23 have been assembled and properlylined up, they are lirmly united into a unitary structure, as by weldingor brazing. Preferably l carry out this operation by placing small wiresot copper or brass adjacent each joint to be established, together withsuitable tluxing medium, and l then subject ythe entire structure tosuthciently high heat so as to cause said copper or brass to llowthrough the adjacent joint, effecting a yfirm juntion to impar-tstrength, and also ettectually preventing steam leakage. rllhisoperation may be carried out in Yan Latmosphere ot hydrogen or otnitrogen, it desired, in order to prevent oxidation and insure a morereliable joint. j

3 is a cross sectional view ot the completed nozzle block on the linelllill ot 2 and clearly shows the members 2l and in juxtaposedrelationship, together with the broad portion 38 et one member 2&3 andthe narrow tapering portion 39 ot an adj acent member 28., theseparti-tion members being shown as suitably received in the slots 36-36and 37-37.

rihe structure eescr-ibed to this point constitutes a nozzle block otarc sha-pe, having nozzle *transversely therethrough 'for projectingsteam a row ot' radial blading, but obviously the generic principles maybe employed in conjunction with radialtlowfblading by the use ot asuitable arc- AShaped nozzle block having steam passages `passingtherethrough inclined to the 'radius thereof. Thus, in Fig. G, I show anozzle block made up .ot coinpleniental haflves 45 and delining .anozzle space 47 therebetween, this nozzle space being sub-divided byappropriate diaphragm members iS-118 into appropriate steam passages.`ln Fig. 7 l show the member l5 in side elevation, and it will be notedthat the surface -theneot is mil-led away as indicated in Fig. .8 todefine a portion ot a steam passage Vat 49 together with a partitionholding groove 5() (also shown in Fig. 7

rlhe partition members 48 are illustrated Ain Fig. 9 and their function:and meth-od of vinsertion are apparent trom the foregoing description.

@liviously the structure ot' Figs. 6., 7, 8 and '9 may be modified todischarge steam either inwardly or outwardly .against a row of axiallydisposed blades as ordinarily employed in radial-now turbines.

lin the subjoined claims, l shall employ the term Ljoined by tus-ion ina generic sense to deline a joining otzmembers by welding,'brazing orotherwise, as may be found necessary or desirable in order to form aunitary structure of great strength and with freedom from leakage.

Thus, by forming two segments se as to abut against each other and byperforming milling or gear cutting operations on their abutting faces, Iam enabled to form nozzle passages symmetrical with respect to astraight line tangent, for example, to the blade carrying wheel uponwhich the nozzle is to operate, resulting in a compact, durable andefficient structure.

It will be apparent from the foregoing description that I may, withgreat facility, modify the number and shape ofthe nozzle passages in adesired nozzle block in order to suit the particular conditions allwithout carrying in stock a wide variety of patterns or other expensiveparaphernalia.

`While I have shown my invention in but two forms, it will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications, without departing from thespirit thereof, and I desire, therefore, that only such limitationsshall be placed thereupon as are imposed by the prior art or as arespecifically set forth in the appended claims.

l/Vhat I claim is:

l. A nozzle block for fluid pressure turbines embodying two abuttingmembers defining anozzle spa'ce and partition members extending insubstantially straight lines transversely of the two abutting members todefine individual nozzles.

2. A nozzle block for fluid pressure turbines embodying two abuttingmembers defining a nozzle space, slots extending in substantiallystraight lines transversely of the two abutting members, andsubstantially straight partition members located in the slots to defineindividual nozzles.

3. An expanding nozzle for a fluid pressure turbine embodying two wallmembers diverging from each other and two partition members carried bysaid wall members and lying in parallel planes.

4. A nozzle block for fluid pressure, turbines embodying two abuttingwall members formed to present a series of converging diverging passagesextending in substantially straight directions transversely of the wallmembers, slots provided in the wall members between the passages, andpartition members in the slots and together with the wall membersdefining individual nozzles.

5. An expanding nozzle for action against a row of radial blading in afluid pressure turbine comprising two wall members spaced apart in aradial direction and diverging, the one from the other, in the directionof fluid flow, and a pair of partition members carried by said wallmembers so as to lie in parallel planes and defining with said wallmembers a nozzle passage.

6. An expanding nozzle for action against a row of radial blading in afluid pressure turbinecomprising two wall members vspaced apart in aradial direction and diverging, the one from the other, in the directionof fluid flow, and each provided with a pair of slots flanking saiddiverging portions, respectively, and a pair of sub'stantially straightparallel partition members having their edges received in said slots andwith said divergent members defining a nozzle passage.

7. A nozzle block for fluid pressure turr bines adapted to dischargefluid against a row of radial blades and embodying an annular outer`segment, an annular inner segment nesting therein, said segments beingslotted in their abutting faces to define inner and outer nozzlewalls,`respectively, and partition members joining said segments todefine distinct nozzle passages.

8. A nozzle block for fluid pressure turbines embodying two membersabutting in a surface normal to the plane of blade travel, complementalslots in the abutting faces of said members to define certain of thewalls of the nozzle passages and septum members embraced between saidabutting members to define the respective nozzle passages.

9. A nozzle block for fluid pressure turbines adapted to discharge fluidagainst a row of radial blading and comprising an outer arc-shapedmember having a portion of its inner face cut away to Aform .a portionof a nozzle space, and the wall of said cutaway portion being formed ina succession of nozzle passages diagonally disposed to the plane of theblade travel each defining a portion of an inlet chamber, a throat sideand thereafter flaring outwardly toward the blades, an inner arc-shapedmember having a complemental portion of its outer face cut away to formthe remainder of said nozzle space and the wall of said cut-away portionbeing formed in a succession of diagonally disposed nozzle passages eachdefining a portion of an inlet chamber, a throat side and thereafterflaring inwardly toward the blades, and a plurality of partition membersjoining said arc-shaped members between said successive surfaces,respectively, and forming therewith a plurality of expanding nozzles.v

10. A nozzle block for fluid pressure turbines adapted to dischargefluid against a row of radial blading and comprising an outer arc-shapedmember having a portion of its inner face cut away to form a portion ofa nozzle space and the wall of said cutaway portion being formed in asuccession of nozzle passages diagonally disposed to the plane of bladetravel each defining a portion of an inlet chamber, a throat side andthereafter Haring outwardly toward the blades, an inner Aarc-shapedmember having a 'complemental portion of its outer lace -cut away toform the remainder of said nozzle space andthe wall of said cut-awayportion :being `formed in a succession of ydiagonally disposed nozzle.passages each defining a portion 4.olf an inlet chamber, a throat sideand thereafter liaring inwardly toward the blades, each pair .ofadjacent surfaces being lseparated by a relatively deep, narrow slot ineach of said .arc-shaped members, and a .plurality of partition membersjoining -said arc-shaped members and having their edges received .insaid deep slots, respectively, said 'partition members with the adjacent:toi-med surfaces defining a succession of expanding nozzles.

ill. A nozzle block for a huid pressure turbine provided with asuccession of nozzle passages therethrough diagonally disposed Yto itheplane of 'blade travel, the walls separating said nozzle passagesextending substantially ,in a straight direction and parallel to eachother land the remaining walls oi? said passages being formed to permitl'lnid expansion While Apassing therethrough.

12. A nozzle .block for a vtluid pressure turbine provided with aplurality of juxta- -posed diagonal nozzle passages therethre l eachpassage 4being of substantially rectangular cross-section and theseparating walls extending substantially in a straight diretenesrecti'on and parallel to eachother, the meinaining walls of saidpassages ,being formed to permit expansion of va fluid passingthefrethrough.

13. ln fluid pressure ',turbine, za fluid nozzle orn substantiallyrectangular Grosssection formed by two opposed members whose opposingaees are formed to provide an inlet chamber 'followed by a divergentpassage and plane parallel septurns jsoin-4 ing said lopposing faces. Y

le. A turbine nozzle comprising two abutmembers with portions -o'f,then` :abutting faces eut away to partially deiine nozzle passages, andpartition members embraced between said members and ydefining with saidcut-away portions distinct nozzle passages, said partition members`tapering to a sharp edge vin .the direction of fluid low.

l5. A turbine nozzle comprising two abutting members with portions .oftheir .abutfaces .cut yaway to :partially denne inozzle passages, andpartition ymembers embraced between said members and delin'i'ng withsaid cut-away portions distinct nozzle passages, said partition memberstapernto a sharp edge 1in the direction of fluid lio-:J and .terminatingshort of rthe exit -surface of fluid from `said nozzle.

ln testimony whereof, I have hereunto subscribed my name this tenth dayof December 1.923.

FRANCIS HGDGKINSQN.

Certificate of Correction.

It is hereby certified that in Letters Patent No. 1,612,436, grantedDecember 28, 1926, upon the application of Francis Hodgkinson, ofSwarthmore, Pennsylvania, for an improvement in Nozzle Blocks, errorsappear in the printed specification requiring correction as Jfollows:Page 1, line 86, strike out the Words cent the first row of movingblades 18 and and insert instead the Words and 18 respectively, saidblade 'rows being; page 2, line 83, for the misspelled Word juntion readjunction; and that the said Letters Pate-nt should be read with thesecorrections therein that the same may conform to the record of the casein the Patent Office.

Signed and sealed this 1st day of February, A. D. 1927.

M. J. MOORE,

[SEAL] .Acting (lofmmz'ssz'oner of Patents.

